diff --git a/modules/nixos/tools/telegraf/default.nix b/modules/nixos/tools/telegraf/default.nix
index f1a2cf6..f20a0bf 100644
--- a/modules/nixos/tools/telegraf/default.nix
+++ b/modules/nixos/tools/telegraf/default.nix
@@ -305,7 +305,7 @@ let
               build_datetime="''${current#*|}"
               build_timestamp="$(${lib.getExe' pkgs.coreutils "date"} -d "$build_datetime" +%s)"
               now="$(${lib.getExe' pkgs.coreutils "date"} +%s)"
-              store_bytes="$(${lib.getExe' pkgs.coreutils "du"} -sb /nix/store | ${lib.getExe pkgs.gawk} '{print $1}')"
+              store_bytes="$(${lib.getExe pkgs.nix} path-info --json --json-format 1 --all --offline --no-pretty | ${lib.getExe pkgs.jq} -r 'map(.narSize // 0) | add // 0')"
 
               printf 'nix generation=%si,configured_packages=%si,store_bytes=%si,build_timestamp=%si,seconds_since_build=%si,build_datetime="%s"\n' \
                 "$generation" \